Heretofore pressure vessel lids have been constructed with safety features such as bleeder valves and pressure sensitive latches to prevent over pressurization of the vessel as well as to prevent the opening of the lid while the vessel is pressurized. However, a problem arises when, due to user neglect, either a bleeder valve is not properly adjusted or the latch is not properly closed during pressurization. Upon such conditions, a tragic accident could occur after pressurization if the latch or bleeder valve, which was improperly adjusted, opens rapidly. Such an event could cause the vessel to disburse its liquid and injure people nearby.